Die forging compound



United States PatentO DIE FORGlNG COB [POUND Lee N. Hudson, Sr., and Theodore C. Foin, Chicago, Ill., assignors to The Hodson Corporation, a corporation of Delaware No Drawing. Application July 19, 1952, Serial No. 299,907

13 Claims. (Cl. 252-30) The present invention relates to improvements in die forging compounds intended for application to hot forging and piercing dies and to other tools for use in the hot forging of metals, and for application to the metal being worked in such operations. In particular it relates to aqueous die forging compounds intended for the aforesaid application.

Die forging compounds of the prior art generally are more or less stable dispersions of graphite in a hydrocarbon vehicle, usually a light paratfin distillate oil. In theuse of these prior art compounds in a conventional hot forging operation where the metal to be forged is heated to a temperature of about 2200 F. and is then inserted in. the die pot of a die press which has been preheated to a temperature of about 300800 F., the hydrocarbon vehicle flashed off and ignited on contact with the hot metal being forged, thus affecting deleterionsly the properties of the forging compound and in addition creating a considerable amount of smoke and fire. These prior art die forging compounds have their greatest objections when applied to the die pot of a vertical forge pressbecause in that die pot the heat causes the vehicle to flow downwardly, carrying with it substantial amounts of graphite, thus leaving in the upper portions of the die pot an inadequate and uneven coating of graphite to effect satisfactory lubrication of the hot metal being forged. Not infrequently, the downward flow of the forging compound under the influence of heat resulted in actually denuding the upper portion of the vertical die pot of the necessary lubricant.

The prior art has attempted to overcome the obvious objections of smoke and fire of the hydrocarbon-based forging compounds by using water as the vehicle for the graphite. In these so-called improved compositions, when the water flashed ofi, which is almost instantaneous with the contact of the hot metal and compound, the residual graphite coating has little or no bind or'clink to the metal and readily flakes. This objectional feature of the prior art aqueous graphite suspensions used as forging compounds, makes their use of limited value. In vertical die presses, for example, they have very little real value.

The aqueous forging compound of the present invention is also an aqueous suspension of graphite, but it is free from the defects inherent in the prior aqueous graphite suspensions. The improved aqueous forging compound is characterized by having binding action through a wide range of temperatures, up to about 900-l000 F. and even higher. The binding action is of a positive character and the bond holding the graphite to the metal is tenacious and insures the retention of the desired uniform coating of the graphite over the entire metal surface, even in the die pot liner of a vertical die press, during the forging operation.

The aqueous forging compound of the present invention contains two binders; one, a low temperature binder effective up to temperatures of about 3004 F.,

which are the usual preheating temperatures of the forg ing punch, and the other, a high temperature binder effective up to temperatures of about 9001000 F; and higher, which temperatures are above the usual die pot preheating temperatures. The water in the compound has some effect in causing the graphite to adhere to the hot metal surfaces. In the compound of the present invention, therefore, we have a. composite of three binding actions which initially are effective to adhere the graphite to the hot metal surfaces. With the vaporization of the water there are two and with the volatilization of the low temperature binder there is only one, namely, the high temperature binder. This last binder is effective to insure the proper adhesion of the graphite to the metal surfaces at the higher temperatures during the forging operation where running or draining of the compound, particularly in a vertical die press, was commonplace. The low temperature binder and the high temperature binder, in particular, attain substantially their maximum. effectiveness at, respectively, about 300 F. and about 900 F. Thus, with the forging compound of the present invention, the binding components thereof are triggered into maximum effectiveness at temperatures where bonding is essential but in the past has been lacking.

The forging compound of the present invention contains an agent which has lubricating and anti-welding properties, a low temperature binder, a high temperature binder, a stabilizing and thickening agent, an emulsifier and water. The various constituents of the composition are combined in proportions to provide either a liquid consistency or a viscous consistency such as the consistency of molasses. It is preferredthat the composition have a consistency which. would make it suitable for either dip application or application by means of a spray.

The preferred lubricant and anti-welding agent is graphite in either amorphous, flake or deflocculated form, The particle sizes of the graphite may vary from very fine, say, 1 to 30 microns, up to a coarse mesh, say, of about 200 mesh sizes. Mica and vermiculite may be used in lieu of the graphite.

The preferred low temperature binding agent is hemicellulose where the compound is to be used as a dip, or as a spray on the walls of a die pot liner which have a temperature of up to about 500 to 600 F. Where, however, the compound is to be used as a spray on the walls of a die pot liner having a temperature of about 600 to 800 F., the preferred binding agent is polyacrylic acid.

The preferred high temperature binding agent is kettle bodied fish (menhaden) oil. Other suitable high temperature binding agents are kettle bodied oils such as linseed oil and soya bean oil, blown oil such as fish oils and soya bean oil, and semi-drying and non-drying animal oils, and semi-drying and non-drying vegetable oils such as castor oil and peanut oil.

The preferred stabilizing and thickening agent is bentonite. The particle sizes of the bentonite may vary widely from extremely fine mesh, about 1 to 25 microns,

to coarser material of from 300 to 400 mesh sizes. Sodium alginate and sodium carboxymethyl cellulose may be used in lieu of the bentonite.

The preferred emulsifying agent is polyethylene glycol monooleate having a molecular weight of 400. The same material in molecular weights of 200 and 600, may also be used. In general, any emulsifying agent may be used, but the preferred emulsifying agents are of the non-ionic type such as the fatty acid esters of polyhydric alcohols or of ether alcohols, for example, glycerol monostearate, and the esters of ethylene glycol, di-, and tri-ethylene gly-' col, and polyethylene glycol. These may be made either by esterifying the glycols or by treating the fatty acids 3 with ethylene oxide, as described in United States Patents Nos. 1,914,100, 2,043,922 and 2,231,128, and French Patent No. 842,943. Other emulsifying agents which may be used are the alkylolamine soaps of fatty acids, rosin acids, and naphthenic acids, the mahogany sulfonates, and the sulfated oils.

The graphite or other lubricant may vary from to 30% by weight, the low temperature binder from 2 to by weight, the high temperature binder from 1 to 15% by weight, the stabilizing and thickening agent from 2.5 to 6% by weight, the emulsifying agent from 0.15 to 2.5% by weight, and water in amount to make up 100% by weight.

The preferred composition for a dip application or a spray application on parts having a temperature of up to about 500 to 600 F., is as follows:

This composition is prepared as follows: 0.75 part by weight of the polyethylene glycol monooleate (M. W. 400) is added to 5 parts by weight of the fish oil and heated to 250 F. with stirring. The heated mixture is added slowly to 68.05 parts by weight of water at room temperature with agitation until completely emulsified. 3.2 parts by weight of bentonite are slowly added and the agitation is continued until the bentonite is completely swollen and dispersed, at which time 3 parts by weight of hemicellulose are stirred in and finally parts by weight of fiake graphite are added. The whole is then agitated vigorously until a homogeneous mixture results.

The preferred composition for a dip application or a spray application on parts having a temperature from about 600 to 800 F., is as follows:

Although the present invention has been described with particular detail in connection with a preferred illustrative example, it is to be understood that it is not to be limited to the details of the example given, since these may be varied as indicated in the specification without departing from the spirit and scope of the accompanying claims.

We claim:

1. A die forging composition comprising, on a weight basis, 5 to graphite, 2 to 15% hemicellulose, 1 to 15% of kettle bodied fish oil, 2.5 to 6% bentonite, 0.15 to 2.5% polyethylene glycol monooleate, and the balance water to 100%.

2. A die forging composition comprising, on a weight basis, 20% graphite, 3% hemicellulose, 5% kettle bodied fish oil, 3.2% bentonite, 0.75% polyethylene glycol monooleate and 68.05% water.

3. A die forging composition comprising, on a weight basis, 5 to 30% graphite, 2 to 15% hemicellulose, 1 to 15% of kettle bodied fish oil, 2.5 to 6% bentonite, 0.15 to 2.5% of an emulsifying agent, and the balance water to 100%.

4. A die forging composition comprising, on a weight basis, 5 to 30% of a lubricant of the class consisting of graphite, mica and vermiculite, 2 to 15% hemicellulose,

4 1 to 15% of kettle bodied fish oil, 2.5 to 6% bentonite, 0.15 to 2.5% of an emulsifying agent, and the balance water to 5. A die forging composition comprising, on a weight basis, 5 to 30% of a lubricant and anti-welding agent of the class consisting of graphite, mica and vermiculite, 2 to 15% hemicellulose, 1 to 15% of a high temperature bonding agent of the class consisting of animal and vegetable semi-drying and non-drying oils, 2.5 to 6% of an emulsion stabilizer and suspending agent of the class consisting of bentonite, sodium alginate and sodium carboxymethyl cellulose, 0.15 to 2.5% of an emulsifying agent, and the balance water to 100%.

6. A die forging composition comprising, on a weight basis, 5 to 30% graphite, 2 to 15% polyacrylic acid, 1 to 15% of kettle bodied fish oil, 2.5 to 6% bentonite, 0.15 to 2.5% polyethylene glycol monooleate, and the balance water to 100%.

7. A die forging composition comprising, on a weight basis, 20% graphite, 3% polyacrylic acid, 5% kettle bodied fish oil, 3.2% bentonite, 0.75% polyethylene glycol monooleate and 68.05% water.

8. A die forging composition comprising, on a weight basis, 5 to 30% graphite, 2 to 15% polyacrylic acid, 1 to 15% of kettle bodied fish oil, 2.5 to 6% bentonite, 0.15 to 2.5% of an emulsifying agent, and the balance water to 100%.

9. A die forging composition comprising, on a weight basis, 5 to 30% of a lubricant of the class consisting of graphite, mica and vermiculite, 2 to 15% of polyacrylic acid, 1 to 15% of kettle bodied fish oil, 2.5 to 6% bentonite, 0.15 to 2.5% of an emulsifying agent, and the balance water to 100%.

10. A die forging composition comprising, on a weight basis, 5 to 30% of a lubricant and anti-welding agent of the class consisting of graphite, mica and vermiculite, 2 to 15 of a graphite binder effective at elevated temperatures up to about 300 to 400 F. of the class consisting of hemicellulose and polyacrylic acid, 1 to 15% of a graphite binder effective at elevated temperatures up to about 900 to 1000 F. of the class consisting of animal and vegetable semi-drying and non-drying oils, 2.5 to 6% of an emulsion thickening agent of the class consisting of bentonite, sodium alginate and sodium carboxymethyl cellulose, 0.15 to 2.5% of an emulsifying agent, and the balance water to 100%.

11. A die forging composition comprising in emulsion form, a lubricant of the class consisting of graphite, mica and vermiculite, hemicellulose, a high temperature bonding agent of the class consisting of animal and vegetable semi-drying and non-drying oils, an emulsifying agent and water, and a thickening agent for said emulsion, in proportions on a weight basis of 5 to 30% of the lubricant, 2 to 15% of the hemicellulose, l to 15% of the bonding agent, 0.15 to 2.5% of the emulsifying agent, 2.5 to 6% of the thickening agent, and the balance water to 100%.

12. A die forging composition comprising in emulsion form, a lubricant of the class consisting of graphite, mica and vermiculite, a low temperature binder effective at temperatures up to 300 to 400 F. of the class consisting of hemicellulose and polyacrylic acid, a high temperature binder effective at temperatures up to about 900 to 1000 F. of the class consisting of animal and vegetable semi-drying and non-drying oils, an emulsifying agent and water, and a thickening agent for said emulsion, in proportions on a weight basis of 5 to 30% of the lubricant, 2 to 15% of the low temperature binder, l to 15% of the high temperature binder, 0.l5 to 2.5% of the emulsifying agent, 2.5 to 6% of the thickening agent, and the balance water to 100%.

13. A die forging composition comprising in emulsion form, graphite, polyacrylic acid, kettle bodied fish oil, an emulsifying agent and water, and a thickening 5 agent for said emulsion, in proportions on a weight basis of 5 to 30% of the graphite, 2 to 15% 0f the polyacrylic acid, 1 to 15 of the fish oil, 0.15 to 2.5% of the emulsifying agent, 2.5 to 6% of the thickening agent, and the balance water to 100%.

References Cited in the file of this patent UNITED STATES PATENTS 268,546 Sawyer Dec. 5, 1882 FOREIGN PATENTS 458,156 Canada July 19, 1949 

1. A DIE FORGING COMPOSITION COMPRISING, ON A WEIGHT BASIS, 5 TO 30% GRAPHITE, 2 TO 15% HEMNICELLULOSE, 1 TO 15% OF KETTLE BODIED FISH OIL, 2.5 TO 6% BENTONITE, 0.15 TO 2.5% POLYETHYLENE GLYCOL MONOOLEATE, AND THE BALANCE WATER TO 100%. 